gcc/testsuite/gcc.dg/Wstringop-overread-2.c

   1 /* Verify -Wstringop-overread is issued for reading more than the maximum
   2    object size but not for writing.
   3   { dg-do compile }
   4   { dg-options "-O2 -Wno-stringop-overflow -ftrack-macro-expansion=0" } */
   5
   6 #define PTRDIFF_MAX   __PTRDIFF_MAX__
   7 #define SIZE_MAX      __SIZE_MAX__
   8
   9 #define NOIPA         __attribute__ ((noipa))
  10
  11 typedef __SIZE_TYPE__ size_t;
  12
  13 void* memchr (const void*, int, size_t);
  14 int memcmp (const void*, const void*, size_t);
  15 void* memcpy (const void*, const void*, size_t);
  16
  17 int strncmp (const char*, const char*, size_t);
  18 char* strncat (char*, const char*, size_t);
  19 char* strncpy (char*, const char*, size_t);
  20 size_t strnlen (const char*, size_t);
  21
  22 void sink (int, ...);
  23 #define sink(...) sink (0, __VA_ARGS__)
  24 #define T(exp)   sink (exp)
  25
  26 NOIPA void test_memchr (const void *p, int x)
  27 {
  28   size_t dmax = PTRDIFF_MAX;
  29   size_t smax = SIZE_MAX;
  30
  31   T (memchr (p, x, dmax));
  32
  33   T (memchr (p, x, dmax + 1));     // { dg-warning "specified bound \[0-9\]+ exceeds maximum object size" }
  34   T (memchr (p, x, dmax * 2));     // { dg-warning "specified bound \[0-9\]+ exceeds maximum object size" }
  35   T (memchr (p, x, smax));         // { dg-warning "\\\[-Wstringop-overread" }
  36 }
  37
  38
  39 NOIPA void test_memcmp (const void *p, const void *q)
  40 {
  41   size_t dmax = PTRDIFF_MAX;
  42   size_t smax = SIZE_MAX;
  43
  44   T (memcmp (p, q, dmax));
  45
  46   T (memcmp (p, q, dmax + 1));     // { dg-warning "specified bound \[0-9\]+ exceeds maximum object size" }
  47   T (memcmp (p, q, dmax * 2));     // { dg-warning "specified bound \[0-9\]+ exceeds maximum object size" }
  48   T (memcmp (p, q, smax));         // { dg-warning "\\\[-Wstringop-overread" }
  49 }
  50
  51
  52 NOIPA void test_memcpy (void *p, const void *q)
  53 {
  54   size_t dmax = PTRDIFF_MAX;
  55   size_t smax = SIZE_MAX;
  56
  57   T (memcpy (p, q, dmax));
  58
  59   T (memcpy (p, q, dmax + 1));    // -Wstringop-overflow disabled
  60   T (memcpy (p, q, dmax * 2));    // ditto
  61   T (memcpy (p, q, smax));        // ditto
  62 }
  63
  64
  65 NOIPA void test_strncmp (const char *p, const char *q)
  66 {
  67   size_t dmax = PTRDIFF_MAX;
  68   size_t smax = SIZE_MAX;
  69
  70   T (strncmp (p, q, dmax));
  71
  72   T (strncmp (p, q, dmax + 1));   // { dg-warning "specified bound \[0-9\]+ exceeds maximum object size" "strncmp" }
  73   T (strncmp (p, q, dmax * 2));   // { dg-warning "\\\[-Wstringop-overread" "strncmp" }
  74   T (strncmp (p, q, smax));       // { dg-warning "\\\[-Wstringop-overread" "strncmp" }
  75 }
  76
  77 NOIPA void test_strncat (char *p, const char *q)
  78 {
  79   size_t dmax = PTRDIFF_MAX;
  80   size_t smax = SIZE_MAX;
  81
  82   T (strncat (p, q, dmax));
  83
  84   T (strncat (p, q, dmax + 1));   // { dg-warning "specified bound \[0-9\]+ exceeds maximum object size" }
  85   T (strncat (p, q, dmax * 2));   // { dg-warning "\\\[-Wstringop-overread" }
  86   T (strncat (p, q, smax));       // { dg-warning "\\\[-Wstringop-overread" }
  87 }
  88
  89 NOIPA void test_strncpy (char *p, const char *q)
  90 {
  91 #if 0
  92   /* Disabled: strncpy calls with an excissve bound trigger both
  93      -Wstringop-overflow and, when the former option is disabled,
  94      -Wstringop-overread.  The latter should probably not trigger.  */
  95
  96   size_t dmax = PTRDIFF_MAX;
  97   size_t smax = SIZE_MAX;
  98
  99   T (strncpy (p, q, dmax));
 100
 101   T (strncpy (p, q, dmax + 1));    // -Wstringop-overflow disabled
 102   T (strncpy (p, q, dmax * 2));    // ditto
 103   T (strncpy (p, q, smax));        // ditto
 104 #endif
 105 }
 106
 107 NOIPA void test_strnlen (const char *p)
 108 {
 109   size_t dmax = PTRDIFF_MAX;
 110   size_t smax = SIZE_MAX;
 111
 112   T (strnlen (p, dmax));
 113
 114   T (strnlen (p, dmax + 1));      // { dg-warning "specified bound \[0-9\]+ exceeds maximum object size" }
 115   T (strnlen (p, dmax * 2));      // { dg-warning "\\\[-Wstringop-overread" }
 116   T (strnlen (p, smax));          // { dg-warning "\\\[-Wstringop-overread" }
 117 }